Boat.



s. M. GRAUMLICH.

BOAT- I APPLICATION FILED 'MAR. l9. I917.

Patented Apr. 16, 1918.

SOLOMON 1V1. GRA'UIVILICH, OF CIRGLEVILLE, OHIO.

BOAT.

Specification of Letters Patent.

Patented Apr. 1%, 1918.

Application filed March 19, 1917. Serial No. 155,791.

To all whom it may concern:

Be it known that I, SOLOMON M. GRAUM- men, a citizen of the United States, residing at Circleville, in the county of Pickaway and State of Ohio, have invented certain new and useful Improvements in Boats; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to new and useful improvements in hulls for boats having peculiar keel and hull construction, which will make them better fitted for speed.

An object of my invention is to provide a speed hull, having its under side at the forward portion, and the after portion concave, and also provided with propellers in each of said spaces.

Another object is to construct the hull so that the boat will have a tendency to plane or glide over the water in a substantially horizontal position instead of cleaving the water massed in front of the bow.

Other objects will appear as the description proceeds.

Like reference numerals are used throughout the specification to describe corresponding parts in which:

Figure 1 is a central vertical longitudinal section;

Fig. 2 is a bottom plan view;

Figs? 4 and 5 are transverse vertical sections taken respectively on the lines 3-3, H and 55 of Fig. 1.

This invention is adapted particularly for use in connection with speed boats commonly known as hydroplanes.

The hull 1 is pointed at the bow 2 and square across the stern 3. The forward portion of the hull 1 is cut concave on the under side at 4%, thereby providing flanges 5 which meet in a point at the bow 2. On the under side of the hull 1 and at the stern is formed a concave surface 6 which extends from the middle portion of the hull 1 to the square stern 3. The portion of the hull 1, between the bow and stern is flat across the bottom, as at 7. A pair of keels 8 extend from a point near the stern 3 of the hull 1, forwardly, and tapering at their forward end where they merge with the flange 5 at a point near the bow 2. These keels 8 are parallel. to each other from their forward ends, to beyond their middle portions, at

which points they begin to diverge outwardly and back to their ends at the stern 3 of the hull l.

A substantially T-shaped member 9 is fastened across the flanges '5 at the forward ends of the keels 8. A socket is formed at the junction of the three arms of the T-memher 9 for receiving the front rudder 10. The arm 11 of the T-member 9 is bent at right angles and has a socket therein as a bearing for the front propeller shaft 13 which has mounted thereon the propeller 12.

Near the stern 3 of the hull 1, at the end of the keels 8 is placed a cross bar or support 14. This bar 1% has a lug 15 bent downwardly'from it, and has a socket therein which serves as a bearing for the rear rudder 16. On the Opposite side of the support 1% is an upturned lug 18 which has a socket in it and serves as a bearing for the rear propeller shaft 19 which has mounted thereon the propeller 20.

It will be readily seen that when power is applied to the propellers, which turn in the same direction, that the water will pocket in the front concave portion of the hull and the front propeller will push it backward. This will cause the middle portion of the boat to always ride on a cushion of water and the front and stern of the boat to be in a substantially horizontal posi- .middle portion of the boat, after which it will then pocket in the concave portion of the stern of the boat, where the rear propeller will force it back and away. The diverging of the keels at the rear will make the boat ride easier and will spread the volume of water out, thereby oflering less resistance to it. It will be noted that the boat constructed in accordance with my invention rides on the surface and does not have to push its bow through the solid water. This makes it a very speedy and eficient type of hull.

Various minor changes in form, proportion and the details of construction may be resorted to within the scope of the appended claims without departing from the spirit or sacrificing any of the principles of this invention.

I claim: 7

1. A boat having a hull, the bottom of said hull being provided with a flat central portionand a concave portion at each end of said central portion, two keels extending substantially the length of the boat and spaced apart to form the sides of said concave portions and said central portion, propellers mounted in said concave portions;

2. A boat having a hull with two keels extending the greater length of said hull, said keels being parallel from forward to the middle of the hull and diverging at their rear, the front portion of said hull being concave on the bottom, a propeller mount'edin said front concave portion, and

.a propeller mounted near the rear of the hull, as substantially described.

3. A boat having a hull with two keels extending the greater length of the boat, the

' bottom of said hull being concave between the keels at its forward and stern ends, the middle portions of the hull being fiat, a

substantially T-shaped member attached in 11 front of the keels and across the forward concave portion, bearings in the said memher for carrying the forward rudder and propeller, a bar attached across sthe stern, lugs on said bar, and bearings in said lugs for carrying the stern rudder and propeller.

In testimony whereof I have hereunto set my hand in the presence of two subscribing; witnesses.

SOLOMON M. GRAUMLIOH.

Witnesses:

C. A. LEIST, RUTH WOLFE.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. 0. 

